The present invention relates generally to headlight tilting system and more particularly to circuitry for such a system which permits accurate and error free selection of the desired angle of the headlight beams.
It has already been proposed to mount a headlight or headlights of an automobile on a frame which is pivotally mounted to the front of the vehicle and control the pivoting of the frames via a push pull cable controlled manually by the driver. This kind of control involves knobs and/or levers movable by the driver. However such arrangements tend to require excessive attention to achieve a desired setting of the headlights which distracts the driver from the all important task of controlling the vehicle.
Another arrangement utilizes a double ended mercury switch which, when not horizontal connects a source of E.M.F. (electromotive force) with an electric motor which operates to return the switch to its horizontal position. The headlight frame is suitably connected to the switch and the electric motor so that upon the longitudinal axis of the vehicle being angled with respect the surface of the road via loading of a heavy weight in the trunk or the like, the mercury switch is triggered to vary the angle of the headlight accordingly.
However such an arrangement has lacked control by the driver especially when travelling up and down hills steep enough to cause the mercury to run to the front or rear of the mercury switch whereby tilting of the headlight beams occurs irrespective of the inclination of the vehicle with respect to the surface of the road.
A third arrangement has been proposed wherein an easily operatable switch is provided for the drivers quick and ready use which energizes an electric motor which moves the headlight mounting frames. This system includes a rotatable electrically conductive member and a series of contacts in sliding contact therewith which combine to effect selection of the position of the headlight mounting frames. However this arrangement has suffered from the drawback that, due to the inertia of the motor armature, the rotatable member is apt to overrun to reconnect the motor with the source of electromotive force. Undesirable disconcerting cyclic repetition of the selection operation is thus apt to occur.
This third arrangement while having solved in part the drawbacks encountered by the first and second mentioned prior art arrangements has lacked precise and mistake free operation. Further mention of this arrangement will be made later in this disclosure under the heading of "detailed description of the invention".